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I'm one of those who's done at least 4 of the rear disk swaps and never added/replaced a proportioning valve. I've never seen the need for one. However, there are some on the Board with more experience than I who insist it's needed for safety reasons. Listen to both sides and decide what you need to do. If someone can post a pic and a location, I'd be glad to try and pull one for you at our local pull a part yards. But I'm in the same boat as you are...I have no clue what it looks like or where in the car to find one.

I'm under the impression that EA81s don't have one at all. The brake balance was achieved by [mis]matching the brake setups accordingly. The posts I've seen on this subject only refer to doing this in EA81s, and that an EA82 valve (even if it had drums) is just fine.

The rear brakes on a subaru are on 2 separate systems, so if you wanted to use a universal one like that, you'd either need 2, or you'd need to completely replumb the system.

Stock EA82 valve is mounted in front of the rear suspension (not far from the fuel pump), and has 4 brake lines going to it. It's not hard to find.

I have a rear disc swap on my brat without the valve. BUT, I have never driven it on the road, at speed, or locked up the brakes. So I cannot speak from experience on that.

But, if the rears really do lock up first, that can be a very dangerous situation. A very small fraction of drivers can INSTINCTUALLY recover from oversteer. Thanks to 100s of hours of ice racing, I do believe I am in that group. But if you have to think about what you need to do to gather the vehicle up and get it going where you want it to go, it's too late.

I'm under the impression that EA81s don't have one at all. The brake balance was achieved by [mis]matching the brake setups accordingly.

Thats correct.

The front-rear adjustment is done via the back drums.

The front discs are self-adjusting.

The adjustment comes with setting the play between the drum and the brake shoe. Adjusted out the rear brakes work less, engaging later, tighten the gap between shoe and drum and the rears do more, engaging sooner.

Ill also say that it can be VERY dangerous to put rear discs (which are self-adjusting) on a rig without the use of a proportioning valve. Engaging the rears too early is a bad, bad thing. Front brakes are designed to do a majority of the braking.

I have a rear disc set up on my Brumby and I don't know if we get a proportioning valve from the factory. I have never had a problem with the brakes since I put the discs on, in fact my ute actually stops now

Ill also say that it can be VERY dangerous to put rear discs (which are self-adjusting) on a rig without the use of a proportioning valve. Engaging the rears too early is a bad, bad thing. Front brakes are designed to do a majority of the braking.

This is what my impression was to. I want to put the valve on, just unsure of how to do so.Hopefully the pages from the manual that tomrhere is sending over will help, but if anyone else has photos or suggestions, I'm more than happy to hear them!

This is what I've heard and worked with too. The rear discs on the L series is a simple swap of the hardware from drums to discs.

I have a rear disc set up on my Brumby and I don't know if we get a proportioning valve from the factory. I have never had a problem with the brakes since I put the discs on, in fact my ute actually stops now

Yeah I don't know Toonga about our brumbys and a proportioning valve. But I've seen many forum members swap to rear discs on the MYs and brumbys without a rear lock up issue. Time to go look at Sunnie the Brumby (who's still living at mine )

I certainly don't see it as a required item but nice to have for sure. The rear disc brakes are certainly less braking than the fronts-still smaller than the fronts, etc. It might be more of an issue on one with 80-82 brakes on an EA71/81 car but otherwise I dont see it being something you can lock the rear without locking the front on.

I certainly don't see it as a required item but nice to have for sure. The rear disc brakes are certainly less braking than the fronts-still smaller than the fronts, etc. It might be more of an issue on one with 80-82 brakes on an EA71/81 car but otherwise I dont see it being something you can lock the rear without locking the front on.

Shawn,

You also mentioned a larger disc from another EA81 model that could be used for the front disc brakes on the BRAT, was it a 84' XT Coupe?

I would just put it on and flush some clean brake fluid through it. If it works once it's all bled out, just clean it up a little and hit it with some rust convertor or POR 15. Just be careful not to damage the rubber on the end of it.

i've had a rear disc setup from a EA82 on my brumby and now have a XT6 setup on it....neither have had a proportion valve and i have never had a problem with the rears locking up prematurely

This is also my experience. The rear discs are much smaller than the fronts so a PV is not required. The braking is unbelievably improved - in fact since going rear discs I've not managed to lock up the wheels once (you can really hear the tyres working to grip the road) whereas I used to have a lot of trouble with lock up on the factory drums...